def docker_network(self) -> Iterator[Network]:
        """
        Return a Docker network.
        """
        client = docker.from_env(version='auto')
        ipam_pool = docker.types.IPAMPool(
            subnet='172.28.0.0/16',
            iprange='172.28.0.0/24',
            gateway='172.28.0.254',
        )
        # We use the default container prefix so that the
        # ``minidcos docker clean`` command cleans this up.
        prefix = Docker().container_name_prefix
        random = uuid.uuid4()
        name = '{prefix}-network-{random}'.format(prefix=prefix, random=random)
        network = client.networks.create(
            name=name,
            driver='bridge',
            ipam=docker.types.IPAMConfig(pool_configs=[ipam_pool]),
            attachable=False,
        )
        try:
            yield network
        finally:
            network.remove() 

def ensure_local_net(
        network_name: str = DOCKER_STARCRAFT_NETWORK,
        subnet_cidr: str = SUBNET_CIDR
) -> None:
    """
    Create docker local net if not found.

    :raises docker.errors.APIError
    """
    logger.info(f"checking whether docker has network {network_name}")
    ipam_pool = docker.types.IPAMPool(subnet=subnet_cidr)
    ipam_config = docker.types.IPAMConfig(pool_configs=[ipam_pool])
    networks = docker_client.networks.list(names=DOCKER_STARCRAFT_NETWORK)
    output = networks[0].short_id if networks else None
    if not output:
        logger.info("network not found, creating ...")
        output = docker_client.networks.create(DOCKER_STARCRAFT_NETWORK, ipam=ipam_config).short_id
    logger.debug(f"docker network id: {output}")